Starting Right –
learning about chemistry
with a 3D periodic table
can't be overestimated
The very first accepted periodic table was based on the premise that a chemical element arrangement makes most sense when arranged in three dimensions, as Alexandre–Emile Beguyer de Chancourtois did in 1862. He aligned the elements in a helix on the outside of a tube, which permitted the periodic elements to be correctly related vertically by property, and having an unbroken numerical sequence of the elements' weights for the first time ever.
Since then, for convenience of printing in books and on posters, the flat chart has become so ubiquitous that most assume that this is the proper representation. That would not be so bad, except that this flawed image (still propagated by the International Union of Pure and Applied Chemistry, the accepted authority) is both confusing and disjointed, and when one begins to associate it with that Periodic Law, the table is also simply wrong
in its many departures from the Law. By providing an unstable basis for future learning, and introducing (reinforcing?) doubt in authority, the credibility of the flat table is challenged.
However...all the varied static and/or interactive flat periodic table charts – for myriad reasons – must be used and relied upon if anyone is to take up chemistry seriously. The way to avoid the establishment of distrust of the content of chemistry teaching is to pre–empt students’ objections to the flat table. The lesson before the introduction of the flat table in beginning chemistry is precisely the time to do this.
Both Scaffolding and Inquiry Based teaching strategies work well to to bridge the informational gap between the usually negative pre–conceptions of the periodic table and its actualities, removing intimidation by the idea of learning the standard periodic table and placing it in proper perspective by revealing its dimensional (historical) roots.
We hope that your Alexander Arrangement of Elements lesson will help your students to learn about the periodic table faster and better, and make your classes easier.